<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
</head>

<body>
    <h2></h2>

    <script>
        var person = {
            level: '2',
            name: '小丽',
            registTime: '2021-11-01',
        }
        var h2 = document.querySelector('h2');
        // 补全代码
        h2.innerText = `尊贵的牛客网${person.level}级用户小丽您好，您已经注册牛客网${Math.floor((new Date().getTime() - new Date(person.registTime).getTime()) / 24 / 60 / 60 / 1000)}天啦~`
    </script>
</body>

</html>